Mortising-chisel



(No Model.)

H. RUPP-ERT. MORTISING CHISEL.

110.571.400. J PatentedN0v.17,1896

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" UNITED STATES PATENT "'O F FICE.

IIENRY RUPPER-T, OF SEBEIVAING, MICHIGAN.

MORTlSlNG-CHISEL.

SPECIFICATION forming part of Letters Patent No. 571,400, dated November 17, 1896. Application filed August 17, 1896. Serial No. 603,027. illomodel.)

T0 aZZ whom it may concern.- Be it known that I, HENRY RUPPERT, a citizen of the United States, residing at Sebewaing, in tlie county of Huron and State of Michigan, have invented certain new and useful Improvements in Mortising-Ohisels; and I do declare the following to be a full, clear, and exact description of the invention, such as will en able others skilled in the art to which it appertains to make and use .the same, reference being had to the accompanying drawings, and to the figures of reference marked thereon, which form a part of this specification.

My invention is a 1l101l3lSlllg-GlllS6l, its object being to provide means for clearing the mortise of shavings during the operation, so that when the mortise is formed no shavings will be left within it, as is common. In the ordinary method of cutting a mortise a large part of the shavings is left within the mortise, and a separate tool has to be taken and inserted into the mortise to drive the shavings out, often wedging the shavings between the tool and the mortise and cracking open the stile'or in some other way ruining the mortise. \Vith the tool hereinafter described the mortise is out clean and smooth, and with the last stroke of the chisel all of the shavings have been expelled.

In the drawings, Figure l is a side elevation. Fig. 2 is a front view. Fig. 3 is a crosssection on line X X of Fig. 1.

l is the chisel, and 2 the cutting-point of the chisel. The rear edge of the chisel is provided with a number of teeth 3 and 4, the points of the teeth extending downward and from the back of the chisel.

Each tooth has a bevel upon one side of the rear of the tooth, sloping toward the side of the chisel, the bevel alternating on the teeth-- that is, the tooth 3 has a bevel upon the front side, as shown in the drawings, and the tooth 4 has a bevel upon the opposite side.

In Fig. 3, 6 represents the bevel in cross section. The points of these teethextending downward, it is obvious that they will out their way through any obstruction, such as the shavings in their path.

It has been common to form a groove in the back of the chisel for the purpose of enabling the chisel to pass more freely through the shavings, the shavings Wedging themselves up through the groove, and serrations have been cut in the edges'of the groove with walls sloping upward instead of downward, as the walls of the teeth do in my tool, for the purpose of engaging and carrying the shavings out of the mortise as the tool is withdrawn, while the object of my tool is to push the shavings through the mortise when the hole is finally cut through.

In operating a mortising-chisel it is com mon to commence at one side of the space to be mortised and cut in with one stroke of the chisel a short distance, the second stroke cutting a little deeper and farther to the opposite side of the mortised space, the third stroke cutting still deeper, and so on until a space has been out out somewhat triangular in form. Then the mortising-chisel is reversed in the chuck, and the first blow commences at the bottom of the mortise already cut and works backward, as previously described, across the mortise, cutting out the balance of the space to be mortised. If, however, the material through which the mortise is to be cut is wide, it is common to cut the mortise but half-way through upon one side and then turn the piece over and cut from the other side in the same manner, reversing the tool as before. 'In using my tool, however, it will be noticed that instead of starting the chisel four times in order to complete the mortise, twice upon each side of the mortise, my chisel only makes three starts, twice upon one side and once upon the other, the mortising-machine being arranged so as to give a long stroke to the lever. Therefore when the tool is reversed in the chuck and proceeds to cut its way back across the mortise it is forced clear through the piece, the teeth 3 and 4, as described, engaging and carrying along with the chisel in its downward stroke any shavings that may be in its path. Upon the upper stroke of the chisel any shavings that may have been wedged into the teeth will be forced out by the upward movement of the chisel, the sloping walls of the teeth described aiding the free extraction of the chisel from the shavings.

hat I claim as new, and desire to secure by Letters Patent, is-- 1. A mortise-cleaning chisel comprising a chisel having teeth on the back edge thereof and above the sloping side of the chisel, each tooth cut with its sloping side extending to one side of the chisel, the teeth alternating up the chisel edge, whereby the sloping side of one tooth Will be upon one side of the chisel, the sloping side oi the next tooth above or below upon the opposite side of the chisel, substantially as specified.

2. In a mortise-cleaning chisel, teeth upon the back edge of the chisel the proper distance above the sloping wall of the chisel, the teeth sloping downward and outward, each tooth having from its upward slant a beveled portion extending to the side of the chisel.

In a mortising-chisel, rake-teeth upon the back edge of the chiseheach tooth extending part way across the edge of the chisel and having the beveled wall 6 extending to the side of the chisel, the bevel upon one tooth being opposite to the bevel upon the other, substantially as specified.

4. I11 a inortising-chisel, rake-teeth upon the back of the chisel, each tooth extending part Way across the edge and alternating, substantially as specified.

5. A mortising-chisel having acutting edge, and above the sloping side'of the chisel a number of drag-teeth, each tooth extending part Way across the edge of the chisel with their cutting edges arranged in opposite sides thereof and in opposition to each other, sub stantially as specified.

In testimony whereof I hereunto aflix my signature in the presence of two witnesses.

HENRY RUPPERT. lVitnesses:

JOHN RIEDEL, OLIN PENGRA. 

